Process of making return-bends.



BEST AVAILABLE COlY r vF. HEUSER.

v PROCESS 0F MAKING RETURN BENDS.

1,153,224. l l VPwnwdsept.1&1-,1915.

I F171 f 2 WF1/771K wm Agb E 2 Ey.y G

M11/M5511? T 11m/mma,

609W u@ of w 'ya fm Y Atlarneyx UNITED STATES lPATENT onnicn FRANZ HEUSER, OF MLHEIM-.RUH'R-STYRUM,

GERMANY, ASSIG-NOR, BY MESNE ASSIGNMENTS, TO LOCOMOTIV SUPERHEATER COMPANY, 0F NEW' YORK, N. Y.,

A CORPORATION OF DELAWARE.

Specification of Letters Extent.V

Application led January 27, 1913. A Serial N o. 744,555?.

To fzZZ 0M om, 'it ma? concern Be it known that I. FRANZ ,Hnnsnni a sub ject of the llmperor'of Germany. residing at Mlheim-RuhreStyr-um, Germany, (whose post-oliice address is Mlheim -Rulir Styrum,) have invented certain new and 4useful Improvements in Processes of Making Return-Bends, ot ,whichthe following is a speci'ticationai l My invention relates to a process ,of making what is commonly known asia return or Ypipe bend andr is of particular advantage in connection with the manufacture of superheater elements for smoke tube superheaters. My invention results in the production ot' a bend as a distinct article oi' manufacture to which the vpipes to be joined by said bend may be united by .welding or by any other suitable method.

The object of my invention is to produce ner and with tools of known character.

Briefly described, my invention comprises taking a suitable cap and, by applying presf sure at and near the free end thereof, forming at said free end, a pair of tubular sockets connected by a flange or web. The pipes which are to be joined by the return bend are then united to these sockets by welding or in other suitable manner.

My invention also includes 'one' way ot' producing a suitable'cap upon which to form the tubular socket-s as aforesaid. According to this feature ot' my invention I start with a short piece of circular tubing, then-partially flatten the same and finally close the ends by pressure. preferably by the action of suitable dies.

lll'y improved method of making a return bend results in a i'initary integral structure the dimensions and proportions of which may be quickly and easily changed by startingr with tubing otl any selected diameter and wall thickness andutilizing suitable corresponding dies.

An advantage of my process is that l may, by suitably prol'ioitioning the proper dies,

- substantially thicken and thereby strengthen the wall of the return bend at' its extreme' -Myinvention will be better understood by referring to the accompanying drawings in whichi' Figures 1 and Q represent, respectively, a

tion of a tube and diesjust after the completion of the first step 1n my process; Figs.

' raient-Qa sept. i4, i915.y

ltransverse and a central longitudinal seci Referring to the drawings, a short piece `of circular tube A of suitable wall thickness and diameter, is compressed between dies B to an over all thickness equal to the outer KYdiameter otl the pipes C which areito be united bythe bend. A pair of mandrels D, ot' suitable diameter, are then inserted within and at opposite sides of the flattened tube A to a predetermined depth. Suitably shaped dies B, provided with longitudinalupstanding portions corresponding to the regions of the tube lying` between the two` inandrels, and having lateral grooves struck from the same centers as those of said mandrels,l are then applied and the walls'of thetnbe thereby vcompressed around said mandrels so-as V to form a pair of tubular sockets A. The fiange E which unites these sockets may, preferably, have the two walls ot' which it consists, welded together. The other end of the iiattened tube A is now closedby the useot' suitable dies B2 (Figs. 5 and (i) and then welded. By varying' the dimensions of the dies B2 the wall thickness at the extreme end F ot' the bend: may be made substantially greater. Preferably this thickness gradually decreases as the distance from the extreme end of the bend increases until iin-ally it becomes that of the socket walls.

have described my improved process of making return bends as comprising several different steps to succeed one another in a specified order. This is, however, by' no means essential and these several described steps may be taken in some diii'erent order, or simultaneously. `within the scope of the invention. For example, the tube length Imight be first flattened vand closed at one end and thereupon the sockets Af formed at the other end. 0r, when starting with a 

